Who is the ‘Landowner’?

In a recent decision letter, reference FPS/Z1585/4/23, Inspector Peter Millman considers a s.119 diversion order ‘in the interests of the landowner.’ The landowner is in the process of selling his house, and the ongoing benefit of the diversion would accrue to a prospective purchaser. Is such a purchaser the ‘landowner’? This decision is summarised in Inquiry Issues.